Conversion of naphthenes to paraffins



Sept. 23, 1947.`

A. P. LIEN Erm.

CONVERSION OF NAPHTHENES T0 PARAFFINS Filed Aug. 21, 1944' Sv uw uw mm.km

Patented Sept. 23, 1947 UNITED STATES PATENT ol-Flcs CONVERSION F PARNAPHTHENES T0 AFFINS Arthur P. Lien, Hammond, Ind., and Bernard L.Evering, Chicago, lll., assignorsto Standard Oil Company, Chicago, Ill.,a corporation of Indiana Application August 21, 1944, Serial No. 550,336

10 Claims. (Cl. 26o-676) This invention relates to the conversion ofnaphthenic hydrocarbons to open-chain soparainic hydrocarbons by meansof a hydrogen u- Processes have been proposed for treating gaso'- `vline or gas oil fractions and parafnichydrocarbons of the naphthaboiling range with boron fluoride promotedV by hydrogen `chloride (U. S.2,344,789). Our object is toavoid the difficulties that are inherent inthe use of hydrogen chloride such as complete miscibility of liquidhydrogen chloride with the hydrocarbon, low critical temperature ofhydrogen chloride,k etc. A further object is to provide a process forconverting naphthenes, such as cyclohexane, which are much morerefractory than ordinary gasoline, gas oils or parafhnic hydrocarbons.Another object is to convert low boiling naphthenes into large yields ofisobutane, branched-chain C5,Ce and C7 hydrocarbons and higher boilingnaphthenes, the latter being considerably more Valuable than low boilingnaphthenes because on dehydrogenation they can be converted into anexceptionally high quality high solvency naphtha, y y

A further object of our invention is to provide an improved method andmeans for eecting con. versionof naphthenes with a hydrogenfluorideboron fluoride catalyst in the presence of added hydrogen andfor expeditiously and almost quantitatively recovering catalyst fromproduct and lay-product streams so that make-up catalyst requirementsare reduced to a minimum. A further object is to provide a method andmeans for increasing the yields of desired products by recyclingparticular fractions of the resulting products. Other objects oftheinvention will be ap-rv parent as the detailed description thereofproceeds.

In practicing our invention We employ at catalyst which `consistschiefly of hydrogen'uoride but which contains about 1 to 40 weightpercent (based on hydrogen iiuoride) preferably to 20 weight percent ofboron fluoride. Such catalyst may contain av trace ofwater, i. e'. about.01 to 1% but preferably not morethan about 3%. Our naphthene chargingstock together with recycled material is preferably contacted with alarge mass of liquid catalyst in the presence of added hydrogen at atemperature Within the approximate range of 150 to 450 F., preferably250 to 350 F., and under a total pressure of 600 to 3000, preferably1200 to 2000 pounds per 'square inch. The catalyst phase in the reactionZone may constitute about 20 to 70% by volume of the total contentthereof. The time of contact will depend of course upon temperature,catalyst composition,

amount and concentration of catalyst and intimateness of contact andother factors and in a continuous process it may range 'from a fewmlnutes to several hours, e. g. about .01 to 4 hours. The space Velocityin a system'wherein a large amountl of catalyst is retained in areaction zone may be in the approximate range vof .1 to 4 usually about.5 to 1 volumes of total charging stock per hour per volume of catalystin the reaction zone.`

The amount of hydrogen may be in'the approximate range of 100 to 600,preferably about 200 to 400 cubic feet per barrel of stock charged. Thecatalyst to hydrocarbon ratio in the total charge entering the reactionzone may be within `the approximate range of .05:1 to .5:1 and forexample may be of the order of about .1:1. The reaction mixture isseparated into a lighter hydrocarbon fraction and a heavier catalystfraction, the bulk of the latter being retained in' or returned to thereactor. Fluorides are removed from thehydrocarbon product fraction andit is then subjectedv to distillation for obtainingan isobutane stream,an aviation gasoline stream (consising essentially of branched-chainparaffin hyl drocarbons) and one o'r-more relatively high boilingnaphthene streams for recycling or rfor use in the manufacture ofspecialty products.

Since boronfluoride is an expensive reagent it is essential thatitslosses be minimized.Y When light hydrocarbon gases such as methane mustbe purged from the system th'e problem of avoiding boron fluoridebrlosses is considerably augmented. In our invention we absorb the tailgases'from the hot settler following the reactor and/or from the boronfluoride stripper in anv absorber liquid which may be relatively coolincoming hydrogen fluoride maintained at suflicient pressure so vthatthe boron 'fluoride is absorbed or uid or gaseous state.

` sorber liquid is an intimate mixture of an aromatic hydrocarbon, suchfor example as toluene or ethyl toluene, with hydrogen fluoride becausematerial, dissolved catalyst components, aromatics, etc.) is reduced toa relatively low pressure and heated to about 90 to 200 F. to partiallydecompose the complex and drive oil! hydrogen iluoride and small amountsof boron uoride.

The heated material is then allowed to settle for the separation andrecovery of any aromatic hydrocarbons. The remaining material is then "iheated to a higher temperature of about 200 to 500 F. for decomposingany complex present and thus recovering residual boron uorlde andhydrogen fluoride which may be absorbed, com"- pressed or otherwise-returned to the reactor.

The invention will be more clearly understood from the followingdetailed description read inV conjunction with the accompanying drawingwhich forms a part of this specification and which is a schematic flowdiagram of our improved continuous conversion process.

A naphthenic hydrocarbon such as cyclohexane, alkyl cyclohexanes, alkylcyclopentanes or mixtures thereof with each other or with otherhydrocarbons is introduced from source I by pump I I through line I2.The charge is as rich in naphthenes as is commercially feasible and itmay consist of a pure hydrocarbon, a relatively narrow boiling naphthenefraction or a wide boiling naphthcne fraction. The charge is preferablyrelatively free from olens in order to minimize the possible formation'of alkyl iluorides and to minimize alkylation. Aromatics in the chargenecessitate an increased load on the catalyst recovery system but oursystem provides a method and means for simultaneously extractingaromatics from charging stock and thereby provides a unique system forhandling charges containing aromatics as well as naphthenes. Theconditions of our process are rather drastic for paraillnic hydrocarbonsand the charge should therefore not contain large amounts thereof. Theinvention is particularly useful for the conversion of so-callednaphthenic slop" cuts from virgin gasoline and it may be applied to anaphthenic gasoline, kerosene, gas oil or heavier fraction. In thisparticular example, the charge consists essentially of cyclohexane. Thecharge is admixed with a recycle stream from line I5. passed throughheat exchanger I8, admixed with catalyst from line .I1

and introduced in line I8 at a low point in reactor I8.

The reaction may be eected in any suitable type of reactor on abatchwise, multiple batch,

4semi-continuous or continuous basis but weprefer to employ a continuousprocess with a tower-type reactor and to eect the conversion by passingthe charging stock upwardly through the column of catalyst maintained inthe liquid phase either with or without mechanical agitation. Thereactor may be of the type generally used for effecting alkylation ofoleilns with isoparamns as exemplified by U. S. 2,238,802 or it may beof the type described in U. S. 2,349,821 for effecting isomerization ofparaillns. It may be about 5 to 50 feet in height and should be designedto withstand a maximum operating pressure which with the hightemperatures may be as high as 3000 pounds per square inch. Before thereaction is initiated the reactor may be illled about half tothree-fourths full of catalyst and heated by any conventional means toreaction temperature.

Hydrogen is introduced into the reactor through line I3 preferably inamounts within the approximate range of 200 to 800 or about 400 cubicfeet per barrel of naphthenes entering the reactor through line I8. Thecatalyst in this specific example is hydrogen fluoride containing about10 weight percent (based on said hydrogen fluoride) of boron fluoride.For each volume of hydrocar bon introduced into the reactor we mayintroduce about .05 to about .5, e. g. about .1 volume of the catalystmixture, the bulk of this mixture being introduced through line I'Ialthough a portion of it may be introduced through line 20. A largerratio of catalyst to oil is required when the charging stock containsaromatics because the solution of aromatics in the catalyst inthereactor tends to decrease catalyst activity and necessitates catalystwithdrawal, recovery and recycling at an 'increased rate. With asubstantially anhydrous charging stock a trace of water may be addedand/or a small amount of aqueous hydrogen iluoride-boron fluoridethrough line 2| so that the catalyst in the reactor will contain about.01 to 1% -but not substantially more than 2 or 3% of water.

The reactor in this case may be operated at a temperature of about 300to 350 F. or about 330 F. and a pressure of the order of 1500- 1800pounds per square inch. The charging stock passes upwardly through theliquid column of catalyst ln the reactor and the bulk of the catalystseparates from the eilluent product stream in the upper part of thereactor althoughisome catalyst material is carried with the effluentproduct stream through line 22 and cooler 23 to settler 24. Catalystmaterial which settles out in this settler may be returned by lines 25and 28 to the reactor. In this particular case the space velocity in thereactor may be about 1 volume of hydrocarbon charging stock per hour pervolume of catalyst in the reactor.

The settler 24 may be operated at substantially reactor pressure and atsuillcient elevation so that the liquid catalyst may ilow by gravityback to the reactor. Alternatively we may employ a pressure reducingvalve in line 22 and operate the settler at a much lower pressure, forexample of the order of about 200 to 400 pounds per square inch, inwhich case a pump will be employed in line 25. Separated gases may bewithdrawn through lines 21 `and 28 .to absorber 28. The product streampasses through line 30 to boron fluoride stripper 3| which is providedwith asuitable reheating means or reboiler 32 at its base. Line lll maybe provided with a suitable pressure reducing valve or pump dependingupon the relative pressures in settler 24 or stripper 3| respectively.The stripper may operate at a'pressure of about 200 to 300 pounds, forexample about 250 pounds per square inch, and suillcient heat issupplied to insure the removal of substantially all of the boronfluoride which passes by line 33,-compressor 34 (when necessary) andline 28 to the base of absorber 28. We prefer to operate the stripperand absorber at such temperatures and pressures that the use ofcompressor 84 may be eliminated. Make-up boron fluoride may be suppliedfrom source 35 and introduced into the system by compressor 38 to line28. l

After removal of boron fluoride the product stream passes by line 8l toazeotropic distillation still 88 which is provided with a suitableheating means or reboiler 88 at its base and which may likewise beprovided with reilux means at its top. A butane-hydrogen fluorideazeotrope passes overhead through line 40, through. condenser 4I tosettler 42 which is operated at as low a temperature as can be obtainedwith available cooling water, preferably, well below 100 F. Thecondensed azeotrope separatesinto a heavier hydrogen fluoride layerwhichis withdrawn by line 43 to hydrogen fluoride storage tank 44. The upperbutane layer is returned as reflux by line 45 and pump 46 to still 38and eventually passes downwardly with the product stream. Any propane orlighter gases may be vented through line 41; such lgases should containno boron fluoride but if they do they may be compressed 'if necessaryand introduced through lineY 28 to absorber 29.

If the product stream withdrawn from the base of azeotropic still 38through line 48 is substantially free from alkyl fluoride and hydrogenfluoride it may require no special treatment for fluoride removal. Aco-nventional bauxite or equivalent treating system 48 is howeverpreferably employedl at this point to insure the removal of any tracesof boron fluoride, alkyl fluorides or hydrogen fluoride which may bepresent.

The product stream is then introduced by line 48 into stabilizer ordebutanizer tower 49 which is provided with a suitable heater orre-boilerk50 at its base and suitable reflux means 5I at its top. Inthis and other fractionating towers any conventional heating and coolingmeans may be employed and in actual practice the reflux is usuallyobtained by condensing the overhead and returning at least a part of theresulting condensate to the top of the tower. A butane stream iswithdrawn overhead through line 52 and it will consist chiefly ofisobutane, which is valuable for producing isooctane by alkylation withbutenes and for other purposes. l

The debutanized product stream then passes by line 53 to fractionatingtower 54 which is likewise provided with a reboiler at its base and a..

hence usually desirable. However, if itis desired to decrease isobutaneproduction and increase the production of Cs-Cs branched-chainparaffinic t hydrocarbons we may recycle a substantial reflux means atits top and which is operated to take overhead branched-chain parafllnichydrocarbons containing about 5 to 6 or '7 carbon amount of isobutanethrough line 52'.

Recycle rates as high as 1 or 2 volumesof liquid lisobutane per volumeof naphthenes charged to the reactor greatly retards the formation ofbutanes and particularly lighter gases in the conversion step.

I Relatively spent catalyst material may be withdrawn from the reactorthrough line 65 or from settler 24 through lines 25 and 66 andthencepassed through pressure reducing valve 61 to decovery drum 68 whichispreferably operated near atmospheric pressure, for example at about 5pounds gauge pressure and at a temperature of the order of 90 to 200 F.but usually not substantially higher than about 150 F. Under theseconditions hydrogen fluoride and some boron fluoride passes up throughline 69 and it may pass directly through condenser 10 to receiver 1I.Boron fluoride .may be withdrawn from the top of receiver 1I throughlline 1I to line 20. Hydrogen fluoride may be pumped via line 12 tohydrogen fluoride storage tank 44. If there is a tendency for moistureto accumulate in the system we may introduce the hydrogen fluorideboronfluoride mixtureA from line 69 into silverlined distillation column 13which is provided with heating means 14 andy we may take substantiallyanhydrous hydrogen fluoride and boron uoride overhead through line 15,and condenser 10 to receiver 1I, returninga portion of the con- -densatethrough line 16 to serve as reflux. An

aqueous hydrogen fluoride-boron fluoride solution may be withdrawn fromthe base of column ',13V through line 11 and withdrawn from the sysatomsper molecule, i. e. Ya fraction boiling from about 10 to about 190"v F.When the conversion conditions or time or Contact are not sucient toinsure the substantial absence of cyClohexane and methyl cyclopentanefrom the product stream the overhead fraction may have an end point ofthe order of about 130 to 140 F. thus limiting the overhead to a productconsisting chiefly of isopentane, neohexane and diisopropyl.

The stream withdrawn from the base oftower 54 through line 56 tofractionating tower 51 will' tern through line TB'althOl-,lgh a smallpart thereof. may be returned through line 2|r by pump 19 the reactor.

, drum 6B below about 200 E. and preferably below ated to form specialsolvency naphthas of relatively low volatility. We may recycle theoverhead from tower 51 through lines 58, 59 and I5 or we may withdrawthis fraction from the system through line 60 for isomerization inaseparate system or for other uses. An intermediate fraction may bewithdrawn through line 6I and may be recycled if desired. The highboil-` ing fraction withdrawn through line 52 may either be recycledthrough lines 59 and|5 or may be about 150 F. the complex is notcompletely decomposed and the only boron fluoride evolved will be thatcontained in solution in the catalyst and loosely bound in complex`material. Some boron fluoride may simply pass along with the hydrogenfluoride to storage tank 44, but any undissolvedA boron fluoride may behandled via line 1 I Y After such hydrogen fluoride and boron fluoridehave been removed therefrom, the remaining spent catalyst material iswithdrawn through line 80 to settler 8| wherein an upper aromatichydrocarbon layer may be recovered from the lower complex layer andpassed by line 82, pump 83 and a bauxite system 82f for fluorideremoval. By removing a portion of the hydrogen fluoride and boronfluoride from thc spent catalyst material aromatic hydrocarbons heldinsolution as a loosely bound hydrogen fluoride-boron fluoride complex areliberated and by employing the settling or separation step aconsiderable amount of The complex and tarry material which settles outin settler 8i is withdrawn through line 84 to drum 85 which is providedwith heating means 86. This drum is operated at about atmosphericpressure or higher and at a temperature of the order of 230 to 500 F. ormore under which conditions the remaining complex is decomposed andboron iluoride and hydrogen iluoride are liberated. The liberated boroniluoride and'hydrogen uoride may be compressed by compressor 81 andreturned by lines and I8 to reactor I9, but are preferably introducedthrough line 20' to the base of absorber 29, the latter arangementoffering the advantage of providing better control on the amount and,composition of catalyst entering the reactor. A tarry residue iswithdrawn from the system through line 88.

Make-up hydrogen fluoride may be added to the system from source 88 tostorage tank 44. Hydrogen iluoride is pumped from this storage tank bypump and passed by line 9| to the upper part of absorber 29 which mayoperate at a pressure which may be as high as 1000 pounds per squareinch and in this particular example may operate at about 240 pounds persquare inch. At such pressures and at the relatively low temperature ofthe order of about 100 F, or lower the boron iluorideis absorbed in orloosely bound to the hydrogen fluoride but the hydrocarbon gases areunabsorbed therein and may be vented fom the top of the absorber throughline 92. By this means losses of boron fluoride are substantiallyprevented while the system is being purged from methane and any otherlight gases which may tend to accumulate therein. It should beunderstood that make-up hydrogen fluoride may be introduced directlyinto the top of the absorber and that line I3 and/or. I2 may likewiselead to the absorber rather than to a hydrogen fluoride storage tank.

Our invention is not limited to the use of hydrogen iluoride as anabsorber, but it is important to note that absorption systems of thetype used for hydrogen chloride in isomerization plants are not suitablefor boron uoride recovery, particularly since it is desirable to ventany propane through line 92 rather than from line Il.

We have discovered that a mosteffective absorbent for boron iiuoride isan intimate mixture or solution of an aromatic hydrocarbon such astoluene, ethyltoluene, diethylbenzene, or vthe like with hydrogenfluoride. It appears that boron fluoride chemically reacts with suchmixture to form a complex which is soluble in liquid hydrogen fluoride.By utilizing such complex formation to remove boron uoride, it may beseparated from extraneous gases at atmospheric pressure, so thatcompressor 81 may be eliminated as well as compressor 34.

An eiective method of operation is to introduce enough C7 to Cnaromatics from line 6l to the upper part of absorber 28 to maintain aliquid hydrocarbon layer above the acid level in the absorber. Intimatemixing can be obtained vby spraying hydroiluoric acid laterally ordownwardly into this aromatic layer (or by any other means) so that anyboron fluoride not absorbed in the lower part of tower 29 will reactwith the intimate mixture in the top thereof to form complex and bepositively prevented from leaving the absorber with extraneous gases.The resulting complex is scrubbed out of the Amixture by incominghydrogen fluoride and carried as a solution therein with the catalystleaving the absorber through line I1.

Results obtainable by the use of our invention have been demonstrated incomparative batch runs carried out in a 1500 cc. carbon steel bombfitted with a 1'725 R. P. M. mechanical stirrer and a bleed-off tubeterminating at a point well above the catalyst level, allowing readyremoval of supernatant hydrocarbon from the reaction mixture. Run A wasmade by simply contacting cyclohexane with hydrogen 'iluoride-boroniluoride catalyst at a temperature of about 330 F. for approximately onehour in the absence of added hydrogen. Run B was under substantially thesame conditions as run A except that it was effected under a hydrogen'pressure of about 1600 to 1800 pounds per square inch; in order tomaintain such hydrogen pressure at reaction temper- Y ature hydrogenhad'to be added five times during the run, since considerabe hydrogen(about .98 mol) was consumed. Run C was under substantially the sameconditions as run B except that the time of contact was about 31/2 hoursinstead of only 1 hour; here again hydrogen had to be added from time totime and about twice as much hydrogen (2.0 mols) was consumed. The

specific conditions employed in each of these runs and the nature anddistribution of products obtained therein are set forth in the followingtable:

Run A B C Conditions:

cyclohexane, cc. 700 700 H i600-1800 i550-i800 390 370 370 39 39 39 350333 340 l. l 50 l 60 210 5. 0 6. 6 I8. l l. 5 2. 0 3. 6 3. 0 4. l 3. 68. 0 16. 8 i7. 5 3.0 18. 0 l5. 2 0. 0 18.0 l2. 7 0. 0 2. 0 2. 5 l. 2 6.5 6. 6 7. 8 y 1. s 2. o 2. 4 l Dlmethylcyclohexane l2. 5 13. 7 l2. lBottoms (alkyl napbthenes) 24. 0 i7. 8 30. 7 H1 Consumed, cu. ft 0.78 l.58 Wt. per cent Condensbles 1 12.6 16. 4 41.3 l Total Parailin yield.Wt. per cent. 1 42. 6 83.3 Ratio: Liquid Parans/Condensibles l. 23 1. 60l. 02

l This difference in contact time was unintentional. does not nullilythe positive nature of the results.

2 Substantially i-Ci.

Particular attention is directed to the fact that the parafiinic productin run A (eiected in the absence of hydrogen) totaled 28.1 weightpercent as compared to 42.6 weight percent in run B where hydrogen waspresent. In run C wherein the contact in the presence of hydrogen waseffected for a prolonged contact time the total yield of parafnsincreased to 83.3 Weight percent. On a volume percent basis the totalyield of paraiilns in run C amounted to 104 volume percent based oncyclohexane charge. Another noteworthy and very remarkable fact is thatthe cyclohexane completely disappeared in run C indicating conversion ofthe original charging stock.

From the above tabulation it will be seen that the use of hydrogenwithout materially changing contact time resulted in a 50% increase inthe total weight percent parailin yield and that more specically itresulted in practically doubling the production of Cs paramns other thanneohexane, at the same time showing a marked increase in the productionof isopentane, neohexane. etc. The ratio of liquid Panam@ f 15.0..;.QlldnSbleS i was 'nce'sedn 19111 .1-23- in the .y absence. of..hydrogen to 9160 ,in the the presenteQthdQeen-LI Inspttelpf the. fattthat-the weight agitent.. 0.1.....0edensibls-.(Chier isabuteeei was.merkedla increase@ there. .was lilrewisa.. a. substantial increasein the.production :f.xpen..ten.e$.al1dleganes moet ref. whitih'fwere y0f.breathed-Chain. 'struttura The higher maletillaryvttiht-Ilapllthtnfts122061168@ tramuta more valuable thant'yclehexaae.vorftheprodution of hieh-.S01vnynaphtha (by.dehydrogenatini and theywmay, be specifically. rutilized .for this .orotherl purposes; by recyclingthe higher boiling alkyl naphthenesjwecanproduce still further amounts of normally liquid branched-chainparailins and isobutane.

While we have describedffin considerable detail a specific example of 4our continuousprocess and have set forthv results vobtainable by the useof our invention it should be understood that the inventionI is Avnotlimited to this specific example or the conditions described inconnection therewith since other modications and alternative operationconditions will be apparentfrom the above detailed description to .thoseskilled in the art. s l We claim: l

. 1. A continuous process for converting naphthenes to parains whichcomprises contacting a charging stock containing asubstantial-,proportionfof aromatic hydrocarbons and naphthenichydrocarbons with a hydrogen fluoride-boron fluoride catalyst containingbetween about 1 and about 40 weight percent of boron fluoride, based onthe hydrogen uoride, at a temperature between aboutl50 andfabout 450 F.in the presence of added hydrogen, under a total pressure of 600 to 3000pounds per square inch in a reaction zone, maintaining intimate contactof said charging stock and catalyst in said reaction zone for a periodof about 0.01 to about 4 hours while maintaining in the reaction zone anamount of catalyst within the approximate range of 20 to 70 volumepercent of the total reactor contents therein, whereby the reactorcontents separate in situ into an upper hydrocarbon phase and a lowercatalyst phase containing extracted aromatic h ydrocarbons, removingsaid lower catalyst phase from the reaction zone, removing dissolved andloosely bound catalyst from said phase, thereafter separating aromatichydrocarbons from said phase, subsequently separating from said phase acatalyst complex containing firmly bound hydrogen fluoride and boronfluoride, thermally decomposing said complex to regenerate hydrogenfluoride and 'boron fuoride, and recycling catalyst separated from saidlower catalyst phase to the reaction zone.

2. A continuous process for converting naphthenic hydrocarbons toparainic hydrocarbons which comprises contacting a charging stockcontaining a substantial proportion of naphthenic and aromatichydrocarbons in a reaction zone with hydrogen and a body of liquidhydrogen fluoride-boron uoride catalyst containing between about 1 andabout 40 Weight per cent of boron fluoride, based on the hydrogenfluoride, under conditions of temperature, pressure and time adapted tohydrogenate naphthenic hydrocarbons. removing from the reaction zone aliquid catalyst layer containing an aromatic hydrocarbon, removingdissolved and loosely-bound catalyst from said layer, thereafterseparating aromatic hydrocarbons from said layer, subsequentlyseparating from said layer a catalyst com-"hydrocarb'onf.chargingtstockl 1:.:

.piencontamine.'.1afirmar-boued` hydrgeee-=fti9ride .and bowafuoridefthermally. decaan@ await .complex ato regenerate. .hydrogen timide-gilboronuoride. and regyclling.ctaiystseperated fromy said` catalyst layerfto said reaction zonen Ih'e 'mthodjsoftc0nvert-ineanerihthri9 hayT dmcar.bons.'1rin-fsu bsta iai yield to parainia '113".- drocarbonslcontaining substantially the .'.same

number Offarbon atoms. nthe molec lalwbitfh method. 1comprises-contactingf' charging Statik Containing :a,normallyfliquidmono ciictnapn- Icarbon f'atoms,inclusive,,inthenaphthenic ring about v3000 i pounds perfsquare inchwith added 'hydrogen in an tunount between. abiu'it` A20D-and aboutl 400cubic feet. per-barreloflnaphthenic 1 and about 40 weight per cent `of.boron fluoride,

`based on the hydrogenfluoridaatatemberature between about 150?` F. andabout v450 E. .and a total pressure betweenab'outGOO and 'about 3000pounds per square inch with added hydrogen, and continuing thecontacting with hydrogen until between about 15 and about 30 mols ofhydrogen are consumed per mols of naphthenic hydrocarbons charged.

6. The method of claim 5 wherein the naphthenic hydrocarbon isoyclohexane.

7. The method of converting naphthenic hydrocarbons in substantial yieldto parafinichydrocarbons containing substantially the same number ofcarbon atoms in the molecule, which method comprises contacting acharging stock containing a normally liquid monocyclic naphthenichydrocarbon containing between 5 and 6 carbon atoms, inclusive, in thenaphthenic ring in a conversion zone with a hydrogen uorideboronfluoride catalyst containing between about 1 and about 40 weight percent of boron fluoride,

based on the hydrogen uoride, under elevated f conditions of temperatureand pressure with added hydrogen in an amount between about 100 andabout 800 cubic feet per barrel of charging stock, containing thecontacting until an appreciable amount but not more than about 30 molsof hydrogen are consumed per 100 mols of naphthenic hydrocarbonscharged, and recovering paranic hydrocarbons thus produced.

8. The Lrnethodof converting naphthenic hydrocarbons in substantialyield to paraiiinic hydrocarbons containing substantially the samenumber of carbon atoms in the moleculel which method comprisescontacting a Acharging stock containing a normally liquid monocyclicnaphthenic hydrocarbon containing between 5 and 6 carbon atoms,inclusive, in the naphthenic ring in a conversion zone with a hydrogenfiuoridepounds per square l1 boron fluoride catalyst containing betweenabout 1 and about 40 weight per cent of boron iluoride, based on thehydrogen ucride, under elevated conditions of temperature and pressurewith added hydrogen in an amount between about 100` and about 800 cubicfeet per barrel of charging stock, continuing the contacting until anappreciable amount but not more than about 15 molsl of hydrogen areconsumed per 100 mols of naphthenic hydrocarbons charged, and recoveringc hydrocarbons thus produced.

9. The method of converting naphthenic hydrocarbons in substantial yieldto paraflinic hy-` drocarbons containing substantially the same numberof carbon atoms inthe molecule, which method comprises contacting acharging stock containing a normally liquid monocyclic naphthenichydrocarbon containing between 5 and 6 carbon atoms, inclusive, in thenaphthenic ring in a conversion zone with a. hydrogen fluorideboronfluoride catalyst containing between about 1 and about 40 weight percentof boron fluoride, based on the hydrogen iluori'de, at a temperaturebetween about 150 F. and about 450 l?. and a total pressure betweenabout 600 and about 3000 inch with added hydrogen, continuing thecontacting with hydrogen until an appreciable amount but not more thanabout 15 mols of hydrogen are consumed per 100 mols of naphthenichydrocarbons charged, and recovering parafllnic hydrocarbons thusproduced.

1o. The method of converting naphthenio hydrocarbons in substantialyield to parafnic hydrocarbons containing substantially the same numberof carbon atoms in the molecule, which method comprises contacting acharging stock containing a normally liquid monocyclic naphthenichydrocarbon containing between 5 and 6 'molsV of hydrogen are consumedper 100 mols of naphthenic hydrocarbons charged, and recoveringparafilnic hydrocarbons thus produced.

ARTHUR P. LIEN. BERNARD L. EVERING.

REFERENCES CITED The following references are of record in the file ofthis patent:

Fiuorine in Aliphatic Compounds, Jour. Amer. Chem.. Soc. 58, 882 (1page). (Patent Omce Library.)

